Diodes AL8807 - Manual (Page 5)

AL8807
Document number: DS35281 Rev. 5 - 2
5 of 20
www.diodes.com
March 2013
© Diodes Incorporated
AL8807
Typical Performance Characteristics
(cont.)
LED Current
LED Current
Error
L = 68H, R = 150m
T = 25C, V = 12V
CTRL = PWM, f = 500Hz
1 LED
S
A IN
PWM
0 20 40 60 80 100
PWM DUTY CYCLE
Figure 7. I vs. PWM Duty Cycle
LED
9
8
7
6
4
3
2
0
L
E
D CURRE
NT
ERROR (
%
)
5
1
0.8
L
E
D CURRENT
(
A
)
0.7
0.6
0.5
0
0.4
0.3
0.2
0.1
6 9 12 18 21 24 27 30 36
V (V)
Figure 8. SW R vs. Input Voltage
IN
DS(ON)
15 33
300
270
210
150
30
0
R
(m
)
DS
(O
N)

90
240
180
120
60
V = Open
V = V
CTRL
SET IN
T = 25°C
A
-40 -15 35 60 110 10 85
Ambient Temperature ( C)
Figure 9. SW R vs. Temperature

DS(ON)
V = Open
V = V = 12V
CTRL
SET IN
400
250
150
100
R
(m
)
DS
(O
N)

350
300
200
6 9 12 15 18 21 24 27 30 33 36
INPUT VOLTAGE (V)
Figure 10. Duty Cycle vs. Input Voltage
100
90
80
70
60
40
30
20
10
0
50
D
U
T
Y
C
Y
C
LE
(
%
)
2 LEDS
3 LEDS
L = 68µH
R = 100m
T = 25°C
V = Open
S
A
CTRL

Figure. 11 SW Output Rise Time Figure. 12 SW Output Fall Time